Fourdrinier paper-machine



(No ModeL) P. CURTIS.

FOURDRINIER PAPER MACHINE. No. 260,172. Patented June 27, 18-82.

N. PETERS. Phulc-Lnho mr. washm fo. 0. c.

UNITED STATES PATENT OFFICEO FRANCIS CURTIS, OF HYDE PARK,MASSACHUSETTS.

FOURDRINIER PAPER-MACHINE.

SPECIFICATION forming part of Letters Patent No. 260,172, dated June 27,1882.

Application filed April 22, 1882.

To all whom it may concern:

Be it known that I, FRANCIS Gnarls, aoitizen of the United States,residing at Hyde Park, in the county of Norfolk and State ofMassachusetts, have invented certain new and useful Improvements inFourdrinier Paper- Machines; and I do hereby declare the following to bea full, clear, and exact description of the invention, such as willenable others skilled in the art to which it appertains to make and usethe same,reference being had to the accompanying drawing, and to lettersor figures of reference marked thereon, which form a part of thisspecification.

The primary object of my invention is to provide a machine for themanufacture of athick, soft web, which in the ordinary Fourdriniermachine would be subjected to such pressure as to be injured for thepurposes I intend it, a secondary object of my invention being tosimplify the construction of the machine and lessen to a marked degreethe wear upon the endless wire shake-apron.

Heretofore in Fourdrinier machines the web of pulp, after leaving thewire shake-apron, is led over a vacuum or suction box, thence over aguide-roll, thence deflected downward to and led between a pair offelt-co vered rolls, termed the coucher-rolls, and from these rolls theweb passes to the endless blan ket-a pron, called in technical parlancethe first felt, and so on to the end of the machine.

In the preliminary manufacture of the thick soft material before alludedto, 1 have found that the pressure upon the web between thecoucher-rolls is too great for my purpose-4n fact, defeats the object Ihave in view-and I have also found that the suction or vacuum boxusually employed is not of sufficient capacity to extract the water fromso thick a material as I propose producing. I have therefore, and inthis the essential feature of my invention consists, discarded theeoucher-rolls, employing simply an idle guide-roll or a suction-box inplace of the lower one, and in place of the guide-roll heretoforeemployed in front of thecoucher-rolls I employ a suction or vacuum box,which by preference is a rotaryone, to avoid wear upon the shakeapron.By dispensin g with the coucher-rolls I effect a consid- (No model.)

erable item of economy in avoiding covering them with the felt jacketnow employed, and I simplify the construction of the machine. Moreover Iavoid the injury to the wire resulting from the crushing action of thecoucherrolls.

The drawin gaccom pan ying this specification represents a sectionalelevation of a portion of a Fourdrinier paper-makin g machine embodyingmy improvements.

In such drawing, A represents the stuff-vat; B,the endless woven-wireshake-apron O, the breast-roll, so callcdthat is, the roll nearest thevat A, about which the apron B passes a a a b I) b, &c., the variousguide-rolls, about which the said apron travels; and D, the suction orvacuum box of a Fou'rdrinier machine.

In carrying my invention into practice I omit the upper coucher-rollaltogether, and in place of the lower coucher-roll I employ a simpleguide-roll, E, while in place of the guide-roll now employed in front ofthe coucher-roll I employ a suction-box, (shown at F.) This suction-boxF may be the ordinary stationary flat box; but to lessen the wear uponthe shakeapron B, I prefer that this box shall be a rotary one, asshown.

Heretofore the woven-wire shake-apron has been impelled mainly by thecoucher-rolls. As I dispense with the coucher-rolls, other means must beemployed to drive the apron, and I utilize the breast-roll O for thispurpose by adding meehanism to rotate this roll.

By dispensing with the two coucher-rolls and the employmentin place ofthem of a simple guide-roll, I avoid the heavy pressure upon the web ofpulp universally exerted by the coucher-rollsin Fourdrinier machines,andIam enabled by this means to produce a light, thick, 90 and elasticweb.

To avoid as far as possible tendency to consolidation and hardening ofthe web, I employ in lieu of the ordinary cylinder driers, which haveunbroken smooth peripheries and dry the 9 5 web by continuouscontacttherewith, skeleton driers, which present interrupted orirregular surfaces to the web to allow of passage of air and lessenextent of bearing-surface between the two. Moreover, by dispensing withthe I00 coucher-rolls I avoid the cost of the felt jackets and the lossof time in shutting down the machine to apply them-no small items in theexpense of running a Fourdrinier machine.

It the suction-boxes D and F do not afford sufficient draft to removethe water from the web of pulp,a third one may be substituted for theguide-roll E. In fact, in the manufacture of web for certain purposes Ishall undoubtedly employ a suction-box (preferably rotary) in place ofthe said roll E.

1 claim 1. In a Fourdrinier paper-machine, the combination of thewoven-wire apron, the guide-

